YES YOU COME UNDER GST AND YOU HAVE TO GET REGISTERED BUT REMEMBER IF YOU OPT FOR COMPOSITION SCHEME THEN YOU CANNOT CLAIM INPUT TAX CREDIT.AND CANNOT RAISE A TAX INVOICE. HOWEVER BILL OF SUPPLY CAN BE ISSUED INSTEAD.

Also please note that composition scheme is only for PPL dealing in goods but in your case you might not opt for composition scheme as you are providing service to your customers so gst @18% will be applicable.